DESCRIPTION (Applicant's Abstract): A variety of mammalian and nonmammalian animal models are currently used in research designed to ultimately improve human health. In recent years, genomic tools have become increasingly important for the molecular genetic analysis of important biological questions. However, aside from the mouse, there are rather few genomic resources available for important vertebrate model organisms such as the frogs Xenopus laevis and X. tropicalis and the zebrafish Danio rerio. Genomic tools are needed to make these models more useful. Recognizing this lack of genomic tools for model organisms, the NIH has organized a number of workshops to address this issue. Several important recommendations have arisen from these workshops. The construction of new, full-length cDNA libraries was considered highly important by members of the Xenopus community. The goal of this project is to construct and make generally available a set of normalized, full-length cDNA libraries from the emerging vertebrate model organism Xenopus tropicalis. These libraries will be constructed identically and in the same expression vector capable of directing expression of individual cDNAs in transfected cells, tissues or embryos, and microinjected embryos. Bacteriophage polymerase promoters flanking the cDNA will enable the production of sense or antisense mRNA for use in microinjection experiments, in situ hybridization and to direct in vitro protein production. EST sequencing of these libraries will facilitate genetic mapping approaches that will greatly increase the utility of X. tropicalis as a vertebrate model organism. These libraries will be made freely available to the research community at modest cost and will provide an important resource required to jump-start research in Xenopus tropicalis. In addition, they will be provided to the ongoing model organism EST project directed by Dr. Steve Johnson at Washington University of St. Louis. It is expected that the availability of these libraries and the data derived from them will serve to facilitate progress in the adoption of Xenopus tropicalis as an important vertebrate model system.